A. Time course for an ODN-directed RNA cleavage assay with MBP-HRHgtC employing the standard ODNs that bind internally in the DRF+ substrate. B. RNA stability during an RNaseH assay employing wildtype MBP-HRHgtC and its active site mutant MBP-HRHgtC(D702A/E731A) employing the standard ODNs that bind internally in the DRF+ substrate. C. Interpretation of the data. S, substrate; P1, product 1; P2, product 2; DE, MPB-HRHgtC(D702A/E731A); −, non-complementary control ODN; +, complementary ODN; grey line, ODN; black line, DRF+ RNA; dashed line, degraded RNA.